I have a 2000 Neon and I am having a PO420 Code that is making the Engine light come on and I need to find out wheter my car is california emmisions or not or if that will even make the engine light come on I got a converter replaced but it is Universal and i have been told that universal ones suck and will make it stay on and my car rough idles and stalls occasionally I had someone tell me it might be the 02 sensors so i am deciding to replace them to see if it works but they got the Ultra low emmision ones and the regular ones and i need to figure out which ones to get .Does it matter wheter the car is California emmisions??Can i get it changed to Federal emmisions??

 

most all newer cars meet ca emmissions so that dont matter to much....... the cat will however. So here is how to know, take a look at your cat and look to see where the downstrwam o2 sensor is located, if its in the cat (in the middle) then more then likly your sensor is bad, if it is above or below the cat (in the exhaust pipe) the the sensor in that place will set off the cell light.

If its in the pipe one fix would be to take it back to the exhaust shop and tell them that the cat they put on was illegal (its federaly illegal to replace a oem cat with one not meeting the same emission standards) and maby they will fix it. Other wise you can do the defouler trick and that will get it. take a look, let me know i can explan the defouler trick! (only cost $2-$3)

 

The downstream one is in the pipe after the cat.

 

yeah, thats not the right cat, thats for a obd 1 computer, thats why it didnt cost that much, a obd 2 cat cost like $400 - $500, you can try the fouler trick. PM me if ya want it!

 

Since when does a cat cost $500?